Malicious PDF — malware analysis report

Static analysis result for SHA-256 3efdb1f7573a672c…

MALICIOUS

PDF

83.4 KB Created: 2021-04-02 04:19:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 28810410be50769fb5097d9714ce12dd SHA-1: 9c0bc0e7a3d074c5a3ad2b4046d91f891e6b9199 SHA-256: 3efdb1f7573a672c7bf6457491968a3e5ac4328a74aba2d1bf280b47f2db302e
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://midufefew.ru/strik?utm_term=justine+marquis+de+sade+summary PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4393779/normal_5ff71c70c3e5f.pdfIn PDF document text
    • http://zespodsvetkoy.site/is_pretty_little_liars_appropriate_for_10_year_olds7gri2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403948/normal_5fe581738f99f.pdfIn PDF document text
    • http://help-feedback-amzn8.xyz/sejenejupilajefupabamofedtpq4i.pdfIn PDF document text
    • http://clebohets.xyz/jivavedobulinejuhaj2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4401714/normal_5ff35c4268c6c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426972/normal_6060893f14ca4.pdfIn PDF document text
    • http://lnstagram-helping.live/can_you_make_sourdough_starter_in_a_bread_machineklzfj.pdfIn PDF document text
    • http://arenda-comp.space/gender_psychological_perspectives_6th_edition_ebookew53t.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://f421159b-d329-41e8-bc42-072bc93e4c50.filesusr.com/ugd/65d6f7_3fe4c07078b84b39b0e0fe7b466f94cb.pdf?index=trueIn PDF document text
    • http://lipegolujodik.epizy.com/attract_woman.pdfIn PDF document text
    • http://kokabine.rf.gd/notigojapov.pdfIn PDF document text
    • https://0ecef3a8-5193-4df1-8dcb-1b7dd0f2be2a.filesusr.com/ugd/e6092c_27de52531ee14ab5bee79af399bc84a0.pdf?index=trueIn PDF document text
    • https://a2fe464c-28d1-4db8-bb2d-552ad9bc2f4d.filesusr.com/ugd/941bb1_2a8e14a13ab0477b9e80279879b96d21.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/redegelesibif/achievement_unlocked_2_guide_unblocked.pdfIn PDF document text
    • https://s3.amazonaws.com/dakebesuvum/tozovojezapozuwajevi.pdfIn PDF document text
    • https://bed2d873-735b-46bb-a8a3-264d0455df4e.filesusr.com/ugd/03ede2_d83227f7a162458995e9c68ec47cc79d.pdf?index=trueIn PDF document text
    • http://ralodanuf.rf.gd/how_to_adjust_rain_bird_sprinkler_valve.pdfIn PDF document text
    • https://02314edc-d025-420b-9d62-795437f25c47.filesusr.com/ugd/4f0fc1_ca5b0a1d17f1423aa93ea78698a63361.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sefiwegegagu/peweduviparavadavokafi.pdfIn PDF document text
    • http://nobubuti.rf.gd/lan_network_diagram.pdfIn PDF document text
    • https://98e80eac-0673-4bf9-a3de-4132461903b3.filesusr.com/ugd/1acd69_f11694d4793c4c20ace1bf348ed34ccc.pdf?index=trueIn PDF document text
    • https://5a20c861-23fd-468b-888e-078c5342874f.filesusr.com/ugd/924841_3d7723d8da924d7281c2cef6ab883bb8.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f794.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF794 4928 bytes
SHA-256: 94e88401d1134438aba627f4d041864a30d72a0531a336a129dd507eb5bbb2fa
font_01_sfnt_off00010826.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10826 12268 bytes
SHA-256: 1e6457384f31fcfcf32c6e712c67135d68288fddeac41e0769f10cdb032afb3c
font_02_sfnt_off00012ffb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FFB 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c